label and counter in custom layout

[Florin Oprina]

Hi all.
I'm trying to create a custom layout. What I want is a style to
display a counter at the beginning of the paragraph, automatically
incremented. In LyX 1.5.3, I followed the customisation guide and
ended up with:
Counter
    Name Mycounter
End
Style My_Style
    LatexType           Command
    LatexName           emph
    LabelType           Counter
    LabelCounter        Mycounter
    LabelSep            xx
    LeftMargin          xx
    ParSkip               0.0
    ItemSep               0.2
    TopSep                0.7
    BottomSep             0.7
    ParSep                0.3
    Align                 Block
    AlignPossible         Block, Left
End

(nevermind the boring \emph{} command, at this stage it is used just
as a placeholder)
This doesn't work as expected, and I don't know what I'm missing. I
was expecting to see a number at the beginning of the line, namely the
value of Mycounter.
Any help is much appreciated.